This invention relates to the detection of microorganisms, more particularly to an apparatus for obtaining samples of microorganisms.
International Publication WO 95/33848 describes a method for identifying bacteria on the basis of characteristic gases and vapours emitted as by-products of bacterial metabolism. The gases and vapours are detected by an array of gas sensing devices, in particular arrays based on semiconducting organic polymers.
One very important source of such bacteria are samples obtained in a swab of some sort. The present invention provides a single apparatus having a dual use i) as a swab and ii) as a integral part of a gas sampling system for subsequent investigation by gas analysis.
For the avoidance of doubt, the term xe2x80x9cgasxe2x80x9d is understood to encompass any species in the gas phase, including vapours from volatile liquids.
According to the invention there is provided microorganism analysis means comprising:
a flow-through arrangement into which a microorganism-containing sample may be introduced;
a headpsace connected or connectible to gas analysis means;
the headpsace being connected to the flow-through arrangement so as to be affected by the sample.
The analysis means may comprise:
a tubular member; and
porous means disposed at one end of said tubular member and communicating therewith so that gas may be flowed through said swab means and said tubular member, the gas flow carrying gases evolved from said microorganism-containing sample therein.
The apparatus may further comprise a receptacle into which said tubular member and swab means may be disposed.
The swab means may comprise a polyethylene mesh or a porous ceramic.
The apparatus may farther comprise a culturing medium, which may be a gel disposed on the surface of the swab means. The gel may be an agar gel.
The swab means may include a layer of cotton wool or gauze.
The tubular member may be disposed in a cap, the cap forming a seal with the receptacle when the tubular member and swab means are disposed therein. The cap may comprise a gas port.
Gases evolved from said microorganism-containing sample may be entrained in a flow of gas which enters the receptacle via the gas port and exits the receptacle via the tubular member.
Gases evolved from said microorganism-containing sample may be entrained in a flow of gas which enters the receptacle via the tubular member and exits the receptacle via the gas port. The swab means may be disposed in a liquid culturing medium.
The flow-through arrangement may comprise a filter on which microorganisms may be collected from a sample flowing through the arrangement. The filter may be a micro-gauge filter.
The flow-through arrangement may, however, comprise an affinity column, which may be connected to a headspace for gas analysis or which may be subject to a washing flow carrying the released microorganism to a headspace generating arrangement.